https://lists.qt-project.org/pipermail/development/2022-May/042437.html
release note:
https://code.qt.io/cgit/qt/qtreleasenotes.git/about/qt/5.15.4/release-note.md
source packages in download.qt.io:
https://download.qt.io/official_releases/qt/5.15/5.15.4/
https://download.qt.io/official_releases/QtForPython/pyside2/PySide2-5.15.4-src/